Same here!
My XW had a live-in BF within 3 months of me moving out, which violated the "no sleepovers when kids are in the house" morality clause she insisted on in the temp judicial order governing separation.
She coyly refused to answer any questions when I demanded to know who was picking up our kids.
she had, a month or two prior to that, sent me a text begging me to comeback, saying she'd do anything, promised she'd go to therapy to work on herself, etc. which I ignored. Had been burned once before on that.
I later heard through a mutual friend that she told people she sent me that because she didn't want a divorce, but didn't love me, and just wanted me around for our kids' sake.
Then she said she viewed her new BF more or less as a placeholder until she found someone better (they're still together nearly a year later). Poor bastard! at least him being around has cut down on the crazy ranting text messages I get from her. silver lining

What a warm and nurturing partner, wife, and mother eh?